Restaurants and other food service businesses generate tons of waste grease each day, which is captured in a grease trap or interceptor. Waste grease of this type typically includes used cooking oil, food waste, grease, fats, and oils. When not managed properly, grease trap waste can cause significant environmental problems. Unfortunately, the majority of waste grease is either sent to landfills or disposed of through municipal sewer systems. Most wastewater treatment plants will not accept waste grease because it is difficult to process. Municipalities are attempting to alleviate problems associated with waste grease by implementing strict regulations for its treatment, but these strict regulations have not been met with an increased number of waste grease treatment facilities.
Brown grease is a valuable component of waste grease because it can be used to as a biofeedstock material for making biofuels, but, unfortunately it is difficult to extract from the waste grease. The raw waste grease typically includes lipid, aqueous, and solid components, the percentages of which will vary based on the source of waste grease. The solid components may include food waste, dirt, and debris. The lipid components include fats, oils, free fatty acids, glycerides, and combinations thereof.